Noob question thread! 2020_Summer

I think I might go with these, its been sooooo hard to find full face helmets that arent 300+. Do you know what helmets these are certified under? Also if glasses can fit underneath? :sweat_smile:

Triple 8 makes a downhill helmet I think you can buy off amazon. Predator (Canadian) also makes some.

I think motorcycle helmets are possible a little chunkier, but I know for a fact some of the main differences are that usually a motorcycle helmet weighs more (though this is also really dependent on build material) and moto helmets usually dont have as great a field of view (hence the thicc visors on downhill helmets).

In terms of safety though, idt any skate helmets will be DOT or SNELL approved, if you’re into that. I haven’t compared those certifications to CSPC’s.

Depending on the speeds you ride at, half face might be enough, or if you’re gonna be going something like 20-25+ mph all the time i think the consensus is to use full face?

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I’ve been reading in to a lot of battery stuff but it’s so complex I’m still getting my head around it.
I thought I was slightly knowledgeable regarding battery safety because Ive used 18650s for a few years, boy was I wrong.
Do you know if it is possible to swap a BSC on an already assembled battery or even worth the effort thought? I seen something on here called a loopkey, would that solve the problem since it wouldn’t need a BSC?

Yah hard to say really without some data recorded or knowing how “deep” or low voltage the discharge cycles were. In general if you don’t over discharge a battery and don’t store a battery fully charged for an extended period of time (weeks to months) then you shouldn’t see such a short battery life. Most cells if kept within limits (not charged over 4.2V, not discharged below 3V per cell typically) then they will usually get a few hundred cycles (full charge to discharge) before they get down to 80% or less of their original capacity and are considered near end of life (soon the rest of the capacity will go away as well). If a cell is kept below max charge and above min charge it’s really ideal and should result in the most cycles. It could be the case that the battery was shipped full and died and early death as a result or it could be you over discharged it because the BMS didn’t cut off the power early enough and over-drained the battery. Like @xsynatic said it’s kinda just guesswork without more details or logging of the charge state at start and end of rides.

For some context I’ve used Lipos and 18650 based batteries and in both cases you should be getting at least a hundred cycles out of the battery so long as it isn’t physically damaged or over discharged/charged. Over discharging a battery can significantly take cycles out of it, or shorting it for a substantial amount of time, lots of things can cause damage to a given cell and make a whole battery appear to be shot (and is basically dead without some very careful surgery)

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I haven’t checked the voltage yet, the problem only really started today. :frowning: before this it was only charging inconsistently which I should have taken as a warning (sometimes it would turn green after an hour, other times a few hours)

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Regarding fixing it too, you could replace the BMS or whatever term you’re used to using for the balance circuitry for the battery but would suggest checking out this thread:

You’d want to check out each of the cells if possible (via balance lead connections or otherwise with a voltmeter) to make sure things are good. For the most part the biggest risk working with 18650s is shorting something especially once your series connections are made since it is a relatively high voltage thing then and with low resistance shorting across the +/- can deliver a lot of amps and become an unintentional spot welder.

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Thanks both for the replies by the way,
that’s a super informative post so thank you for educating me.
Here’s hoping the replacement battery they send out will be a little better. I’ve seen a few posts like mine in the past week, so it could have possibly been a bad batch which they have spotted and are sending replacements out if the board was purchased within a time frame.

I do have one more question though. (I’m a pretty huge noob right now) but does this mean I’d be able to buy a more reputable battery granted it fits inside the encasing?
thanks again both!

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Thanks for the battery thread/post, I’ll check it out in the morning on my commute to work!

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Yes, we have many very talented battery builders here that can make a battery to the exact spec you want. Size, cell, bms, everything.

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I did see some of the beautiful work that people on here have made. Impressed is an understatement!
If the new battery sent from the manufacturer even shows any signs like this one did, I’m definitely going to try and get one done by one of the many talented people here :slight_smile:
Honestly after the 70 miles I did on the board I definitely can’t go back to a manual now!

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I just went for another ride today and I noticed the same hiccups again in the motors. Its only when I accelerate, it seems like its struggling (single motor) but i wasn’t really pushing it. Should I be worried?

personally id tear it down and start trouble shooting. I wouldn’t want it to suddenly stop on me. Not sure what it could be though tbh. Have you tried re-uploading the firmware and running motor setup again?

Soo… i swapped the guts last night from my old wood deck to a hummie deck, put everything together, stick the receiver with tape on the outside of the cutout and from the first ride i noticed that the throttle stutters. Even this morning, fresh out of the station, i turn on the remote and hear 3-4 hfi sound beeps, like the remote struggles to find a neutral point… is there a way to see the uart throttle input in vesc app?

I’m thinking it’s either bad signal (carbon fiber eh…), shitty potentiometer finally bit the dust or the wires going to the receiver don’t make contact well…
Can anyone with a hummie deck tell if they’re facing similar signal issues?

Need help diagnosing this belt issue. My guess is that the belt is too tight. Sounds normal with the belt off. The belt has no play so I thinks it’s too small — it’s a 280 on a TB mount reversed

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Okey, I got a question. Im going to buy a charger for my 12A battery. My bms does 10Amps balance charge. Can I buy 2 4-5 amps chargers and connect them in parallel? This seems drangerous as shit but no idea I I can do that to get higher amps

Are you using 5M belts? What gear ratio, I can not see how you fitted a 280 belt in there, I needed at least a 310 with small gears

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Video doesn’t work, but based on sound there’s way worse things happening in there. Loosen up the belts!
Also, check how much play the motor can has to the stator. Ideally it should be 0, but if you already ran the belts super tight for a while every piece is out of tolerance already

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Yah don’t do that. Problem is any voltage difference in the transformers that convert AC to DC will result in current flow out of one and into the other (the voltage will attempt to level out or self balance basically but will never be able to do it if one is always higher voltage output than the other). Personally use a led driver power supply that is rated for 500W of power output and operates at 24V, my balance charger takes up to 36V DC input and is also rated to handle 500W for charging most things, for the metroboards battery I just bought a “fast charger” from them and accept that it takes time but only need to charge it every couple weeks.

If you were to try this I would think safest to use some high power diodes that will let the current flow in one direction mostly unimpeded but stops any “backflow” from one charger pumping voltage so high current starts to flow back into the other.

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Thanks, I knew it was kind of a dumb question because of the inability of chargers to keep exactly the same voltage but just wondering if someone has done it. I will look at your suggestions!! Thanks! :grin:

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I haven’t had any signal issues that I’m aware of. I have a Maytech V2 remote, metr pro, and a smart BMS in mine. BigBen fiberglass enclosure

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